Torque limiting devices are used in a wide variety of applications. One such application is in actuators used in aircraft, where the actuators may be used to deploy control surfaces, for example flaps or slats. Power is transmitted to a plurality of linked actuators from a central power drive unit. Torque limiting devices are used with each actuator to limit the maximum torque delivered to the actuator's output in the case of the deployed surface jamming. Without a torque limiting device, the entire output torque of the power drive unit would feed directly into the jammed component, requiring the relevant structure to be sized to resist such loading. This will result in weight penalties on the aircraft, which is undesirable.
Known torque limiting devices may use multiple interleaved friction plates or a torsion bar system. Whilst these systems are effective in certain applications, there remains an ongoing effort to create alternative forms of torque limiting devices.